See, when I first heard about background-repeat: round; I thought it was something to do with making things circular. But no, it’s about tiling a background image so that nothing gets cut off. The amount of tiling required is rounded to the nearest whole number.

A step-by-step walkthrough of how GitHub has tweaked its Content Security Policy over time. There are some valuable insights here, and I’m really, really happy to see companies share this kind of information.

This is really, really clever. You can’t use generated content (:before and :after) on replaced content. The img element is replaced content …but only when the image actually loads. So if the image fails to load, you can apply specific fallback styles (using :before and :after).

Marco gives a run-down of the basics of getting accessibility right on the web. Nothing here is particularly onerous but you’d surprised how often developers get this wrong (or simply aren’t aware of it).

He finishes with a plea to avoid unnecessary complexity:

If there’s one wish I have for Christmas from the web developer community at large, it is this: Be good citizens of the web, and learn proper HTML before you even so much as touch any JavaScript framework. Those frameworks are great and offer a lot of features, no doubt. But before you use hundreds of kilobytes of JavaScript to make something clickable, you may want to try if a simple button element doesn’t do the trick just as fine!

The transcript of a great talk by Wilto, focusing on responsive images, inlining critical CSS, and webfont loading.

When we present users with a slow website, a loading spinner, laggy webfonts—or tell them outright that they‘re not using a website the right way—we’re breaking the fourth wall. We’ve gone so far as to invent an arbitary line between “webapp” and “website” so we could justify these decisions to ourselves: “well, but, this is a web app. It… it has… JSON. The people that can’t use the thing I built? They don’t get a say.”

We, as an industry, have nearly decided that we’re doing a great job as long as we don’t count the cases where we’re doing a terrible job.

I just had my responsive images epiphany and I’m writing it all down before I forget everything.

Writing something down (and sharing it) while you’re still figuring it out is, in my opinion, more valuable than waiting until you’ve understood something completely—you’ll never quite regain that perspective on what it’s like to have beginner’s mind.

This is a deep, deep dive into responsive images and I can only follow about half of it, but there are some really useful suggestions in here (I particularly like the ideas for swapping out images for print).